I'm curious if the mechanic you now took the vehicle too, has done a thorough diagnosis on the Cylinder #8 missfire, (code po308). There is a small possibility that the wire or plug on that cylinder is defective, but there are other possibilities for the missfire code. Such as the injector on that cylinder, the distributor cap or rotor, if this is the non-DIS version (distributorless ignition) if this is the DIS, there may be a faulty coil, which was a common occurance. I would ask the mechanic how he concluded the ignition wires where bad, and the plugs. What where his kv (kilivolt) readings on that cylinder? What was the resisance reading of the plug wire in question? Often mechanics like to throw a set of plugs and wires after seeing a missfire code, simply because it's the most common reason. If he does have an accurate diagnosis, Unfortunlty you may have ended up with a set of defective plugs or wires, but more commonly the plug is defective, and I would have that replaced first. If the engine does not missfire at all times, I would be sucpicious of another problem, more commonly worn plugs and wires cause a fairly consistant missfire, noticable when driving.

-Rip

If your feeling the hesistation intermitently, I would make sure the mechanic is using an automotive oscilliscope to trace the problematic cylinder. If there is a problem with the compression, ignition, plugs, wires, injectors - this is the only way to troubleshoot, I would be more comfortable of you replacing the plugs and wires again, if your current mechanis can tell you the specifics of the missfire and why he concludes the fairly new ignition parts.

-Rip